I'd estimate building anything that floats in the ocean is about 100x as expensive than a regular building, as the environment is very hostile. The sea is const

I'd estimate building anything that floats in the ocean is about 100x as expensive than a regular building, as the environment is very hostile. The sea is constantly moving, trying to pull your structure apart. There's storms and salt spray. In case of a problem, like a a fire, you can't escape it by just stepping outside. This is why ships are more and more tightly regulated and certified nowadays. Anyway, if this is going to be deployed in a wide scale, there's another issue. You're going to shade the ocean so they will start blocking large amounts of light, and it could be a problem, as they would be limiting primary plankton production. You'd have to place them far away in "the deserts of the sea".